JavaScript Absolute Beginner's Guide

Who knew how simple using JavaScript could be? Make the most of JavaScript—even if you've never programmed anything before. JavaScript Absolute Beginner's Guide is the fastest way to learn JavaScript and use it together with CSS3 and HTML5 to create powerful web and mobile experiences. Learn how to do what you want, the way you want, one incredibly easy step at a time. JavaScript has never been this simple! Here's a small sample of what you'll learn: • Organize your code with variables • Understand how functions make your code reusable • Use the popular if/else statement to help make a decision in code • Learn about switch statements and when to use them • Work with for, while, and do...while loops • Learn how to use global and local scope • Understand what closures are • Learn about the various places your code can live • Understand how to write comments and use good commenting practices • Learn about the basic types of objects you'll run into in JavaScript • Find out that pizza has an educational value beyond just being deliciously awesome • Learn how to perform common string operations • Use arrays to handle lists of data • Learn to create custom objects • Get up to speed on some of the big ES6 changes

Table of Contents:
Introduction     1 Parlez-vous JavaScript?     2 Contacting Me/Getting Help     3 Chapter 1  Hello, World!     5 What Is JavaScript?     7 Hello, World!     8     The HTML Document     8 Looking at the Code: Statements and Functions     11 PART I:  THE BASIC STUFF Chapter 2  Values and Variables     15 Using Variables     16 More Variable Stuff     17     Naming Variables     17     More on Declaring and Initializing Variables     18 Chapter 3  Functions     21 What Is a Function?     23 A Simple Function     24 Creating a Function that Takes Arguments     28 Creating a Function that Returns Data     33     The Return Keyword     33     Exiting the Function Early     34 Chapter 4  Conditional Statements: If, Else, and Switch     37 The If / Else Statement     39     Meet the Conditional Operators     41     Creating More Complex Expressions     44     Variations on the If / Else Statement     45     Phew     47 Switch Statements     47     Using a Switch Statement     47     Similarity to an If/Else Statement     51 Deciding Which to Use     53 Chapter 5  Looping with For, While, and Do…While!     55 The for Loop     57     The Starting Point     61     The Step     61     The Condition (aka How Long to Keep Looping)     62     Putting It All Together     62 Some for Loop Examples     63     Breaking a Loop     63     Skipping an Iteration     64     Going Backwards     64     You Don't Have to Use Numbers     65     Oh, No He Didn't!     65 The Other Loops     66     The while Loop     66     The do…while Loop     66 Chapter 6  Commenting Your CodeFTW!     69 What Are Comments?     70     Single Line Comments     71     Multi-Line Comments     72 Commenting Best Practices     73 Chapter 7  Timers     77 Delaying with setTimeout     78     Looping with setInterval     79     Animating Smoothly with requestAnimationFrame     80 Chapter 8  Variable Scope     83 Global Scope     84 Local Scope     86 Miscellaneous Scoping Shenanigans     87 Block Scoping     87     How JavaScript Processes Variables     90     Closures     92 Chapter 9  Closures     93 Functions within Functions     94 When the Inner Functions Aren't Self-Contained     98 Chapter 10  Where Should Your Code Live?     105 Approach #1: All the Code Lives in Your HTML Document     109 Approach #2: The Code Lives in a Separate File     110     The JavaScript File     110     Referencing the JavaScript File     111 So…Which Approach to Use?     114     Yes, My Code Will Be Used on Multiple Documents!     114     No, My Code Is Used Only Once on a Single HTML Document!     116 PART II:  IT'S AN OBJECT-ORIENTED WORLD Chapter 11  Console Logging Basics     119 Meet the Console     120 Displaying the Console     121 If You Want to Follow Along     124 Console Logging 101     125     Meet the Log Method     125     Going Beyond Predefined Text     127     Displaying Warnings and Errors     128 Chapter 12  Of Pizza, Types, Primitives, and Objects     133 Let's First Talk About Pizza     134 From Pizza to JavaScript!     136 What Are Objects?     138 The Predefined Objects Roaming Around in JavaScript     140 Chapter 13  Arrays     143 Creating an Array     144 Accessing Array Values     145 Adding Items to Your Array     147 Removing Items from the Array     149 Finding Items in the Array     150 Merging Arrays     150 Mapping, Filtering, and Reducing Arrays     151 The Old School Way     151 Modifying Each Array Item with Map     152 Filtering Items     154 Getting One Value from an Array of Items     155 A Short Foray into Functional Programming     157 Chapter 14  Strings     159 The Basics     160 String Properties and Methods     161     Accessing Individual Characters     161     Combining (aka Concatenating) Strings     163     Getting Substrings out of Strings     164     Splitting a String/split     165     Finding Something Inside a String     166     Upper and Lower Casing Strings     168 Chapter 15  When Primitives Behave Like Objects     169 Strings Aren't the Only Problem     170 Let's Pick on Strings Anyway     170 Why This Matters     172 Chapter 16  Numbers     175 Using a Number     176 Operators     176     Doing Simple Math     177 Incrementing and Decrementing     177 Hexadecimal and Octal Values     179 Special Values—Infinity and NaN     180     Infinity     180     NaN     180 The Math Object     180     The Constants     181     Rounding Numbers     182     Trigonometric Functions     183     Powers and Square Roots     184     Getting the Absolute Value     185 Random Numbers     185 Chapter 17  Getters and Setters     187 A Tale of Two Properties     188 Meet Getters and Setters     190     Shout Generator     191     Logging Activity     191     Property Value Validation     192 Chapter 18  A Deeper Look at Objects     195 Meet the Object     196     Creating Objects     197     Adding Properties     197     Removing Properties     200     What Is Going on Behind the Scenes?     201 Creating Custom Objects     205 The this Keyword     209 Chapter 19  Extending Built-in Objects     213 Say Hello to prototype…again—Sort of!     214 Extending Built-in Objects is Controversial     219     You Don't Control the Built-in Object's Future     219     Some Functionality Should Not Be Extended or Overridden     219 Chapter 20  Using Classes     221 The Class Syntax and Object Creation     222     Creating an Object     222     Meet the Constructor     224     What Goes Inside the Class     226 Extending Objects     229 Chapter 21  Booleans and the Stricter === and !== Operators     237 The Boolean Object     238 The Boolean Function     238 Strict Equality and Inequality Operators     240 Chapter 22  Null and Undefined     243 Null     244 Undefined     244 PART III:  Working with the DOM Chapter 23  All About JSON (aka JavaScript Object Notation)     247 What Is JSON?     248 Looking Inside a JSON Object     252     Property Names     252     The Values     253 Reading JSON Data     257     Parsing JSON-looking Data into Actual JSON     259 Writing JSON Data?     259 Chapter 24  JS, the Browser, and the Dom     261 What HTML, CSS, and JavaScript Do     262 HTML Defines the Structure     262 Prettify My World, CSS!     264 It's JavaScript Time!     265 Meet the Document Object Model     267     The Window Object     269     The Document Object     269 Chapter 25  Finding Elements in the Dom     273 Meet the querySelector Family     274     querySelector     275     querySelectorAll     275 It Really Is the CSS Selector Syntax     276 Chapter 26  Modifying Dom Elements     279 DOM Elements Are Objects—Sort of!     280 Let's Actually Modify DOM Elements     282     Changing an Element's Text Value     284     Attribute Values     286 Chapter 27  Styling Our Content     289 Why Would We Set Styles Using JavaScript?     290 A Tale of Two Styling Approaches     290     Setting the Style Directly     290     Adding and Removing Classes Using JavaScript     292 Checking Whether a Class Value Exists     294     Going Further     294 Chapter 28  Traversing the Dom     297 Finding Your Way Around     298     Dealing with Siblings and Parents     301     Let's Have Some Kids!     301 Putting It All Together     302     Checking If A Child Exists     303     Accessing All the Child Elements     303     Walking the DOM     303 Chapter 29  Creating and Removing Dom Elements     305 Creating Elements     306 Removing Elements     314 Cloning Elements     315 Chapter 30  In-Browser Developer Tools     323 Meet the Developer Tools     324     Inspecting the DOM     326     Debugging JavaScript     331     Meet the Console     337     Inspecting Objects     338     Logging Messages     340 PART IV:  DEALING WITH EVENTS Chapter 31  Events     343 What Are Events?     344 Events and JavaScript     346     1. Listening for Events     346     2. Reacting to Events     348 A Simple Example     348 The Event Arguments and the Event Type     351 Chapter 32  Event Bubbling and Capturing     355 Event Goes Down Event Goes Up     356 Meet the Phases     361 Who Cares?     363 Event, Interrupted     364 Chapter 33  Mouse Events     367 Meet the Mouse Events     368     Clicking Once and Clicking Twice     368     Mousing Over and Mousing Out     370     The Very Click-like Mousing Down and Mousing Up Events     372     The Event Heard Again…and Again…and Again!     373     The Context Menu     374 The MouseEvent Properties     375     The Global Mouse Position     375     The Mouse Position Inside the Browser     376     Detecting Which Button Was Clicked     377 Dealing with the Mouse Wheel     378 Chapter 34  Keyboard Events     381 Meet the Keyboard Events     382 Using These Events     383 The Keyboard Event Properties     384 Some Examples     385     Checking That a Particular Key Was Pressed     385     Doing Something When the Arrow Keys Are Pressed     386     Detecting Multiple Key Presses     386 Chapter 35  Page Load Events and Other Stuff     391 The Things That Happen During Page Load     392     Stage Numero Uno     393     Stage Numero Dos     393     Stage Numero Three     394 The DOMContentLoaded and load Events     395 Scripts and Their Location in the DOM     397 Script Elements—Async and Defer     400     async     400     defer     400 Chapter 36  Handling Events for Multiple Elements     405 How to Do All of This     407     A Terrible Solution     408     A Good Solution     409     Putting It All Together     412 Chapter 37  Conclusion     415 Glossary     419 Index     423